"Believe / Kumori Nochi, Kaisei" is ARASHI's 25th single. "Believe" was used as the theme song for the movie Yatterman, starring Sakurai Sho. "Kumori Nochi, Kaisei" was the theme song for the doramaUta no Onii-san, starring Ohno Satoshi. This single was released in three versions, two limited CD+DVD editions and a regular CD only edition with an exclusive song and karaoke tracks. The single topped the Oricon weekly charts and charted for 30 weeks. It sold 656,676 copies in 2009, making the best selling single of the year.